An Indian child receives polio vaccination drops from a medical volunteer during a National Pulse Polio Immunisation (PPI) programme in Amritsar on January 19, 2014. The World Health Organisation (WHO) declared India free of the crippling polio virus on Thursday, making the country's almost two-decade-long, multi-billion-dollar effort one of the biggest public health achievements in recent times. -- FILE PHOTO: AFP

NEW DELHI (REUTERS) - The World Health Organisation (WHO) declared India free of the crippling polio virus on Thursday, making the country's almost two-decade-long, multi-billion-dollar effort one of the biggest public health achievements in recent times.